Down
syndrome
due to a free trisomy 21 may be (in rare cases)
accompanied by presence of an additional sSMC.
Such
cases
are here collected.
Frequency of sSMC plus trisomy
21 among Down syndrome patients (according to {6}): 3 of 25,817 cases with
Down syndrome;
the same paper concludes, that there is no increased
risk of trisomy (21) in carriers of sSMC.
Cases without sSMC
but with Down syndrome (47,+21) from parents with
SMC (47,+mar)
Described in Refs: {9, 18, 19,
20, 21, 22}
case no.
new
|
case no.
old
|
gender/
age at diagnosis
|
studied
material
|
de novo/
inherited
|
GTG-banding result
grade of mosaicism
|
final result
of the sSMC
|
test
methods
|
clinical
symptoms
|
Reference
|
+21-
00-
1 to 3 |
+21-
U-
3 to 5 |
n.a./
n.a. |
n.a. |
n.a. |
48,+21,+mar |
n.a. |
n.a. |
Down
syndrome |
{8}
original literature not available |
+21-
00-
4 |
+21-
U-
12 |
female/
1m |
PBL |
n.a. |
48,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome |
{13} case
4 |
+21-
00-
5 |
+21-
U-
13 |
n.a./
1m |
PBL |
n.a. |
48,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome |
{14}
original literature presently not
available |
+21-
00-
6 |
+21-
U-
14 |
n.a./
1m |
PBL |
n.a. |
48,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome |
{15}
original literature presently not
available |
+21-
00-
7 |
+21-
U-
15 |
n.a./
1m |
PBL |
n.a. |
48,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome |
{16}
original literature not available |
+21-
00-
8 |
+21-
U-
16 |
female/
1m |
PBL |
mat |
48,XX,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome |
{17} |
+21-
00-
9 |
+21-
U-
17 |
n.a./
1m |
PBL |
n.a. |
48,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome |
{18}
original literature not available |
+21-
00-
10 |
+21-
U-
18 |
n.a./
1m |
PBL |
n.a. |
48,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome |
{19}
original literature not available |
+21-
00-
11 |
+21-
U-
19 |
n.a./
1m |
PBL |
n.a. |
48,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome |
{20}
original literature not available |
+21-
00-
12 |
+21-
U-
20 |
male/
prenatal |
AF |
mat |
48,XY,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome
TOP |
{21} case
2 |
+21-
00-
13 |
+21-
U-
25 |
n.a./
1w |
PBL |
familial |
48,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome |
{27} |
+21-
00-
14 |
+21-
U-
26 |
male/
postnatal |
PBL |
familial |
48,XY,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome |
{28} |
+21-
00-
15 |
+21-
U-
27 |
male/
postnatal |
n.a. |
n.a. |
48,XY,+21,+mar[?] |
n.a. |
n.a. |
Down
syndrome |
{29} |
+21-
00-
16 |
+21-
U-
33 |
female/
7m |
PBL |
de novo |
48,XX,+21,+mar |
n.a. |
n.a. |
Down
syndrome |
{30} |
+21-
00-
17 |
+21-
U-
42 |
male/
newborn |
PBL |
familial |
48,XY,+21,+mar
|
n.a. |
aCGH |
Down
syndrome |
{36} case
1 |
+21-
acro-
1 |
+21-
U-
6 |
male/
1m |
PBL |
de novo |
48,XY,+21,+mar
(bisatellited)[?] |
n.a. |
n.a. |
Down
syndrome |
{7} case 6 |
+21-
acro-
2 |
+21-
U-
7 |
female/
1m |
PBL |
de novo |
48,XX,+21,+mar
(bisatellited)[?] |
n.a. |
n.a. |
Down
syndrome |
{7} case 7
|
+21-
acro-
3 |
+21-
U-
8 |
female/
1m |
PBL |
de novo |
48,XX,+21,+mar
(bisatellited)[?] |
n.a. |
n.a. |
Down
syndrome |
{9} |
+21-
acro-
4 |
+21-
U-
9 |
male/
1m |
PBL |
de novo |
48,XY,+21,+mar
(bisatellited)[?] |
n.a. |
n.a. |
Down
syndrome |
{10} |
+21-
acro-
5 |
+21-
U-
10 |
female/
1m |
PBL |
de novo |
48,XX,+21,+mar
(bisatellited)[?] |
n.a. |
n.a. |
Down
syndrome |
{11} |
+21-
acro-
6 |
+21-
U-
11 |
female/
1m |
PBL |
de novo |
48,XX,+21,+mar
(bisatellited)[?] |
n.a. |
n.a. |
Down
syndrome |
{12} |
+21-
acro-
7 |
+21-
U-
47 |
male/
1m |
PBL |
n.a. |
48,XY,+21,+mar[40%]/
47,XY,+21[60%] |
inv
dup (acro)(p10) |
acrocenM |
Down
syndrome |
{0}
provided from Dresden, Germany
|
+21-
02-
1 |
n.a. |
female/
prenatal
|
fibroblasts |
?pat
3/200 cells
|
48,XX,+21,+mar[25]/
47,XX,+21[5] |
min(2)(:p11.1→q11.2:)
|
cenM
subcenM |
Down
syndrome
TOP
|
{0}
provided from Hannover, Germany
|
+21-
04-
1 |
+21-
U-
1 |
male/
1m |
PBL |
de novo |
48,XY,+21,+mar[28]/
47,XY,+21[7] |
min(4)(:p12→q11:)
partial
maternal iso-UPD 4p16 |
cenM
subcenM; UPD-test |
Down
syndrome |
{1} case
10
{2} |
+21-
07-
1 |
+21-
U-
28 |
male/
postnatal |
PBL
(EKF-
cellbank) |
n.a. |
47,XY,+21/47,XY,+mar/
?48,XY,+21,+mar/?
46,XY; mar
in 50% of the cells |
min(7)(:p11.1→
q11.21:)[10]/
r(7)(::p11.1→
q11.21::)[1x]/
min(7)(:q11.21-p11.1:
:p11.1→q11.21:)[9] |
cenM
subcenM |
Down
syndrome |
{0}
provided by Dr. B Zoll, Göttingen, Germany |
+21-
13-
1 |
+21-
U-
32 |
male/
adult |
PBL |
n.a. |
48,XY,+21,+mar[1]/
47,XY,+21[29] |
r(13)(::p1?2→q1?3::)[1]/
der(13)(pter→q?12.11:
:p11.1→q1?3:
:q11.1→p1?1.2:)[2] |
cenM,
subcenM |
Down
syndrome |
{32} |
+21-
13-
2 |
+21-
U-
48 |
male/
adult |
PBL |
n.a. |
48,XY,+21,+mar[1]/
47,XY,+21[29] |
r(13)(::p1?2→q1?3::)[1]/
der(13)(pter→q?12.11:
:p11.1→q1?3:
:q11.1→p1?1.2:)[2] |
cenM,
subcenM |
Down
syndrome |
{0}
provided by Dr. Brecevic, Zagreb, Croatia |
+21-
13/21-
1 |
+21-
U-
29 |
female/
postnatal |
PBL |
familial |
48,XX,+21,+mar[100%] |
inv
dup(13)(q11) or
inv dup (21)(q11.1) |
M-FISH;
cenM
subcen |
Down
syndrome |
{0}
provided by Carme Fuster, Barcelona, Spain |
+21-
13/21-
2 |
+21-
U-
38 |
female/
postnatal |
PBL
(EKF-
cellbank) |
pat |
48,XY,+21,+mar[100%] |
inv
dup(13or 21)(q10) |
cenM,
subcenM |
Down
syndrome |
{0} |
+21-
13/21/18
1 |
+21-
U-
35 |
male/
7y |
PBL |
de novo |
48,XY,+21,+mar[100%] |
der(13
or 21)t(13 or 21;18)(13 or 21pter→13q11 or
21q11.1:
:18p11.21→18p11.32) |
M-FISH,
subcenM |
Down
syndrome |
{37} |
+21-
14-
1 |
+21-
U-
22 |
female/
1m |
PBL |
de novo |
48,XX,+21,+mar[45%]/
47,XX,+21[55%] |
r(14)
negative for D22Z4 and positive for
D14/22Z1 |
FISH with
all available centromeric probes |
Down
syndrome |
{23} case
7 |
+21-
14-
2 |
+21-
U-
36 |
male/
2m |
PBL |
mat |
46,XY,der(14;21)(q10;q10),+mar[100%] |
min(14)(:p11→q11:) |
centromeric
probes |
Down
syndrome |
{31} |
+21-
14-
3 |
+21-
U-
40 |
male/
newborn |
PBL |
mat
for mother see 14-O-q11/2-1 |
47,XY,rob(13;21)(q10;q10),+21,+mar* |
min(14)(:p11→q11:) |
cep probes |
Down
syndrome |
{34} |
+21-
14-
4 |
- |
male/
prenatal |
AF |
mat |
48,XY,+21,+mar |
inv
dup(14)(q11.1) |
ceps |
Down
syndrome |
{0}
provided by Dr. Demuth, Erfurth, Germany |
+21-
14/22-
1 |
+21-
U-
23 |
female/
prenatal |
AF |
n.a. |
48,XX,+21,+r[60%]/
47,XX,+21[40%] |
r(14
or 22)
ring present in 80% of lung tissue |
FISH with
all available centromeric probes |
AMA, TOP,
Down syndrome |
{24;25}
case 23 |
+21-
14/22-
2 |
+21-
U-
24 |
female/
1w |
PBL |
maternal
due to a karyotype 46,XX,t(14;21)
(q11.1;p11.1)* |
47,XX,t(14;21)
(q11.1;p11.1),+21
sSMC
is here the der(14)t(14;21)
(q11.1;p11.1) |
n.a. |
n.a. |
Down
syndrome |
{26} |
+21-
14/22-
3 |
+21-
U-
34 |
female/
2y |
PBL |
de novo |
47,XX,der(14)t(14,21),
+mar[100%] |
47,XX,t(14;21)
(q11.1;p11.2),+21 |
cenM,
subcenM |
Down
syndrome |
{33} case
P-8, {38} |
+21-
15-
1 |
+21-
U-
2 |
female/
at birth |
PBL |
mat |
47,XX,-14,+t(14;21)
(p11;p11),+mar[?] |
inv
dup(15)(q11.2 or q12) |
radioactive
ISH with pML34 |
Down
syndrome |
{3; 4; 5} |
+21-
15-
2 |
+21-
U-
2a |
male/
1m |
PBL |
de novo |
48,XY,+21,+mar[22] |
inv
dup(15)(q10) |
cenM;
subcenM |
Down
syndrome |
{1} case
23 |
+21-
15-
3 |
+21-
U-
44 |
male/
prenatal |
CVS |
de novo |
48,X,+21,+mar[100%] |
inv
dup(15)(q12)
(excl. SNRPN); aCGH: pter-46.95 |
cep, SNRPN;
aCGH |
Down
syndrome |
{39} case
CVS-2 |
+21-
15-
4 |
+21-
U-
46 |
female/
prenatal |
AF |
n.a. |
48,XX,+21,+mar[7]/
47,XX,+21[23] and UPD(15)mat |
min(15)(q11.1)
|
cenM
subcenM |
Down
syndrome;
PWS |
{0}
provided by Dr. Huhle, Leipzig, Germany |
+21-
15-
5
|
sib
of
15-O-
q11.1/1-21
|
n.a./
prenatal |
AF |
n.a. |
48,XX,+21,+mar[?mos] |
inv
dup(15)(q11.1)
|
n.a. |
Down
syndrome |
{0}
provided by Dr. Niemann, Overat, Germany |
+21-
15-
6
|
sib
of
15-O-
q11.2/1-18
|
female/
prenatal |
AF |
n.a. |
48,XX,+21,+mar[?mos] |
inv
dup(15)(q11.2)
|
acrocenM;
subcenM |
Down
syndrome;
PWS |
{0}
provided by Dr. Dufke, Tübingen, Germany |
+21-
15-
7
|
15-
U-
2 |
female/
at birth |
PBL |
maternal |
47,XX,-14,+t(14;21)(p11;p11),+mar[?] |
inv
dup(15)(q11.2 or q12) |
radioactive
ISH with pML34 |
Down
syndrome |
{42-44} |
+21-
15-
8
|
see
McCl-15-N-q11.1/2-1 |
+21-
16-
1 |
+21-
U-
37 |
male/
prenatal |
AF |
n.a. |
48,XY,+21,+r(16)(p11.2q11.2)[11]/47,XY,+21[19] |
mar(16)(:p11.2→q11.2:)
array: 31.65-45.07 MB |
aCGH |
Down
syndrome |
{0}
provided by Dr. S.W. Cheung, Houston, USA |
+21-
21-
1 |
+21-
U-
41 |
male/
4m |
PBL |
n.a. |
47,XY,t(4;19)(p16.3;p13.2),inv
dup(21)(q10),+inv dup(21)(p10) |
inv dup(21)(p10) |
SKY, subcenM |
Down
syndrome |
{0}
provided by Dr. Aniko Ujfalusi, Hungary |
+21-
21-
2 |
+21-
U-
45a |
male/
postnatal |
PBL |
n.a. |
47,XY,der(21;21)(q10;q10),+21,+mar[100%] |
der(21;21)(p11.1;p11.1) |
subcenM |
Down
syndrome |
{0}
provided from Poland |
+21-
21-
3 |
+21-
U-
45b |
male/
postnatal |
PBL |
n.a. |
47,XY,der(21;21)(q10;q10),+21,+mar[100%] |
der(21;21)(p11.1;p11.1) |
subcenM |
Down
syndrome |
{0}
provided by Dr. Vesic, Belgrade, Serbia |
+21-
21-
4 |
+21-
U-
45c |
male/
prenatal |
AF |
n.a. |
47,XY,der(21;21)(q10;q10),+21,+mar[100%] |
der(21;21)(p11.1;p11.1) |
FISH |
Down
syndrome |
{0}
provided by Dr. Vesic, Belgrade, Serbia |
+21-
22-
1 |
+21-
U-
30 |
male/
1m |
PBL |
n.a. |
48,XY,+21,+mar[90%]/
47,XY,+21[10%] |
min(22)(pter→q11.22:) |
cenM,
subcenM; CES-specific probes |
normal
pregnancy, born by sectio cesaraea; Down
syndrome with AVSD and Morbus Hirschsprung |
{0}
provided by Dr. Mazauric, Düsseldorf,
Germany |
+21-
22-
2 |
+21-
U-
31 |
female/
1m |
PBL |
de novo |
48,XY,+21,+mar[10]/
47,XY,+21[30] |
inv
dup(22)(q11.1) |
cenM,
subcenM |
Down
syndrome |
{0}
provided by Dr. Huhle, Leipzig, Germany |
+21-
22-
3 |
+21-
U-
39 |
male/
prenatal |
fibroblasts |
n.a. |
48,XY,+21,+mar[11]/
47,XY,+21[4] |
min(22)(pter→q11.21) |
cenM,
subcenM |
Spontaneous
abortion - maybe due to combination of
trisomy 21 and sSMC |
{35} case
26 |
+21-
0X-
1 |
minX-
p11.1/
1-1 |
female/
postnatal |
PBL |
n.a. |
46,X,+21,+mar[67%]/
45,X[33%] |
min(X)(:p11.1→q11.1:) |
n.a. |
Down
syndrome |
{45} case
6 |
+21-
0Y-
1 |
+21-
U-
43 |
n.a./
prenatal |
AF |
n.a. |
47,X,+21,+mar[15]/
46,X,+21[2] |
min(Y)(pter→q11.1) |
subcenM |
Down
syndrome |
{0}
provided from Poland |
+21-
0Y-
2 |
- |
n.a./
n.a. |
PBL? |
de novo |
46,X,+mar[30]/
47,XY,+21[20] |
min(Y)(:p11.2→q11.221:) |
n.a. |
Down
syndrome |
{41} |
|